The invention relates to a ship rudder control, a so-called autopilot, having a plurality of electronic components that are connected to each other by means of a CAN bus. Due to the enormous importance that the correct rudder position and also its indication to a skipper possesses, there are several copies of sensors, position encoders, and display instruments on all ships.
When using electronic components with a CAN bus, as is customary in automotive engineering, there is the problem that outages of single components are often due to poor functional capability of a bus interface or the cabling or the plug connection of the electronic component to the bus. The effects of such fault events are to be minimized as far as possible.
The bus can further be damaged in its property as data line, it being possible for this damage even to be the reception of an unwanted signal, that is to say this damage may be present only temporarily. So as to avoid that such a bus fails in its entirety despite this, a redundancy through an alternate path has to be provided.
Using two data buses simultaneously is however associated with a very substantial overhead in terms of information transmission, that in particular again is a stress on the bus interfaces.